Hinges for use on folding doors and the like

ABSTRACT

A hinge adapted to low cost production and suited to use in connecting planar panels of folding doors and the like together for swinging movements relative to one another and to and from coplanar relationship, said hinges having plug-type mounting portions insertable into, and securable in precisely located openings that may be jig-bored or prefabricated in the panels prior to installation, thereby to minimize both product and installation cost and to effect proper positioning and alignment of the hinge axes. The hinge is also reversible and interchangeable for use at both top and bottom positions on the door panels, thus to limit inventory of parts and reduce possibilities of errors in assembly or placement.

[ June4,1974

Unite States Patent 1191 Smith 15 mm mN m Wm G M RLM WE bmm D a i m mm BW n n m mm PAA ABSTRACT [22] Filed:

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mit inventory of parts and reduce possibilities of errors in assembly orplacement.

16/ 159 versible and interchangeable for use at both top and 16/ I59bottom positions on the door panels, thus to li l6/l5l 181,843 9/1876Hapgoodm.......v............1....... l 643 218 9/1927 McDonell 3,597,7908/l97l Kellems 14 Claims, 10 Drawing Figures HINGES FOR USE ON FOLDINGDOORS AND THE LIKE BACKGROUND OF INVENTION Traditionally, theinstallation and alignment of door hinges and the hanging of hingesupported doors has required both time and skill. The current trendtoward the use of lightweight folding or bifold doors to afford betteraccess and to limit the space requirements for the swinging of thedoors, as well as the desire for avoidance of the high material andlabor costs associated with large and heavy wood doors, have brought oncorresponding desires with respect to promotions of economies and theadaptations of supporting hardware, including hinges, for-use with thefolding door panels and their materials, structures and manners offabricatron.

As with other doors, the hinges for folding doors must be securelymounted and accurately placed. The hinges should desirably beinconspicuous for most door structures and should not cause appreciablegaps between the door panels when the door panels are in their closedpositions. Also. the hinges and their placement whould be compatiblewith the mounting and operatings of other hardware items used on thedoors.

Usually the hinges are flush mounted on the back faces of the doorpanels, or may be edge mounted using butterfly or butt hinges. lf butthinges are used, costly countersinking is required to avoid an unsightlygap between the adjacent panels of such doors in the closed position.When the panels are fabricated of plastic material, as many are beingmade, countersinking is practically impossible unless done when thepanels are made. Even then, additional fastening elements or means arerequired for securing the hinges to the panels. This affords addedproblems in respect to both mounting and possible loosening during use.In any event, such countersinking and face mounting operations are timeconsuming and expensive.

As a result of the foregoing and other considerations, it has become abasic concept of this invention that hinges with ample strength andruggedness for use on folding doors and the like can be made and mountedto provide only relatively thin exposed portions at very inconspicuouspositions on the top and bottom edges of the door panels adjoinedthereby. In addition, and in accordance with this invention, the hingesmay be fabricated with precisely located and rugged mounting parts andlocating surfaces for securement to panels which are either fabricatedor jig-bored to receive the mounting and locating parts of the hinges.

One of the objects of this invention isto provide a hinge adapted tomounting at the top and bottom ends of planar panels to folding doors toconnect those panels for relative swinging movements to and fromcoplanar relationship about an axis spaced from the panel planes andwhich is approximately coincident with the planes of the adjacent edgesof the connected panels, each said hinge including a pair of unitary andintegral parts connectible to one another for swinging movements andeach of which incorporates mounting and locating elements.

Another object of the invention is to provide a hinge structure adaptedto precise mounting relative to edge and face surfaces of a planar doorpanel by virtue of having as parts thereof a plug-type mounting elementto be pressfitted into a precisely located opening in the door panel,means for limiting the movement of the plug-type mounting element intothe panel opening, and an additional means for engagement with a facesurface of the panel to further establish the hinge part positionrelative to the panel.

This invention further has within its purview the provision of hingesadapted to quick and easy mounting in, and relative to openings andsurfaces in the planar panels of folding doors, which openings areestablished precisely during fabrication of the panels or bored with aidof a suitable jig or guide, and which surfaces are established when thedoor panels are fabricated.

Also within the comprehension of this invention is the provision ofhinges mountable quickly and easily at inconspicuous positions on theplanar panels of folding doors without the aid of additional fasteners,such as screws or bolts, so that the door panels are freely swingablefrom and toward positions in which the panels are closely spaced atadjacent edges and in substantially flush and coplanar relationship toone another.

As another object, this invention comprehends a hinge having parts, eachof which parts is mounted and secured in position by a plug-typemounting element which fits into an opening in a door panel, and whichplug-type mounting elements are each provided with retainingtangs-shaped and constructed to move into the opening in the door panelwith relative ease when the plug-type element is installed therein, butwhich bite into the surface of the opening to retain the plugtypeelement in the opening after installation.

It is also within the purview of this invention to provide hinges suitedto use on folding doors and the like, and the principal parts of whichcan be made by molding from tough and wear resistant plastic material,such as nylon.

This invention has for another object the provision of hinges made ofseparate parts which are each securable to an end surface of a panel ofa folding door adjacent one edge of the panel, and which parts areconnectable for swinging movements about an axis spaced from the panelsconnected thereby, as well as reversible for use at either the top orbottom end surfaces of the panels.

IN THE DRAWINGS:

FIG. 1 is a fragmentary front plan view of a wall segment having a dooropening in which is hung a double bifold door and which is illustrativeof an adaptation of the hinges of this invention;

FIG. 2 is a fragmentary and broken view, drawn to a larger scale thanFIG. 1, and showing an adjacent pair of panels of a bifold'door whichare connected for relatively swinging movements about an axis providedby an aligned pair of the hinges of this invention;

FIG. 3 is a top plan view of one of the hinges depicted in FIG. 2, theconnected door panels being fragmentarily shown;

FIGS. 4a and 4b are front elevational views of two coacting parts of ahinge of the type illustrated herein and embodying a preferred form ofthis invention;

FIG. 5 is a bottom view of the hinge part shown in FIG. 412;

FIG. 6 is a sectional view taken substantially as shown by a line 66 andthe accompanying arrows in FIG. 5;

P10. 7 is a fragmentary sectional view taken substantially as indicatedby a line 7-7 and accompanying arrows in FIG. 6;

FIG. 8 is a fragmentary top view of the portion of the structureillustrated in FIG. I, with the folding positions of door panelsillustrated in dotted lines; and

FIG. 9 is a perspective view of one type of retainer part adapted to usewith the illustrated and preferred hinges.

in the exemplary embodiment of this invention which is shown in theaccompanying drawings for illustrative purposes, a wall 10 has therein adoor opening 12 which may be, for example, the entrance to a closet.Depending upon the width of the closet door opening and the widths ofthe panels used, either one or two pairs of planar panels 13, 14, 15 and16 may be used to provide a closure for the door opening. Anotherfeature of consideration is that narrow panels require less space fortheir swinging movements. it is, of course, a feature of bifold doorstructures that they provide access to the door opening space, and yet,when hung as shown herein, require much less space for single movementsthan a conventional swinging door.

This invention being mainly concerned with a particular type of hingesadapted to the connection of adjoined panels of a bifold door forswinging movements relative to one another, the general structure,movements and operations of other door parts will be considered only tothe extent necessary for a general understanding of the door and itsoperation, with particuiars directed mainly to the hinges, theirstructure, installation and operation.

structurally. the door opening is encompassed by a lintel 17 at the top,jambs l8 and 19 at its opposite vertical sides, and a sill 20 at thebottom. Extending across the top of the dooropening 10, below the lintel17, is a guide track 22 which is usually made of metal having a sectionproviding a support and guiding movements of one edge of one panel (14or 15) of each bifold door linearly back and forth across the top of thedoor opening. The panels (13 and 14, and 15 and id) of each bi fold doorhave adjacent edges 23 and 24, and 25 and 26 connected together forrelative swinging move ments. each about an axis, by for relativeswinging movements, each about an axis, by top hinges 27 and 28 andbottom hinges 29 and 30 respectively; the top and bottom hinges of theconnected panels of each bifold door being axially aligned. Spacedsomewhat inwardly from the outer edge which is adjacent the door jamb(l8 and 19) each outer panel (13 and 16) is supported for swingingmovements about a fixed axisby aligned upperand lower pivots, 32 and 33for panel 13, and 35 and 36 for panel 16; the upper pivots being securedin fixed positions relative to the lintel, and the lower pivots beingsecured in fixed positions relative to the sill.

With this arrangement of pivots, hinges and slides, the panels are inflush and generally coplanar relationship to one another to effectclosure of the door opening. Knobs or handles 36 and 37 are provided onthe exteriors of the mid-regions of the pivoted panels 13 and 16, bywhich the doors are swung between their closed and opened positions.Between such positions, the hinges between adjoined panels swing throughthe position depicted at 28a in HO. 8, and the panels of each bifolddoor pass through the positions shown in dotted lines at 15a and 16a.When the doors are wide open, practically the entire door opening 12 isclear; it being understood that during the swinging movements of thedoor panels, the outer edges of the doors are guided in a linear pathalong the door opening by guides 38 and 39 moving in or on the track 22.

Preferably, bifold doors of the type shown in FIG, 1 are provided, attheir outer and adjoining edges, with an aligner 40 having parts 42 and43 attached at the free or exposed edge regions of panels 14 and i5 andmovable into aligned relationship for engagement for bringing. andholding the panels of the door in proper position at and near the lowerend portion of the door. In addition, and for holding the panels of eachbifold door in coplanar relationship to one another, so that the airpressure within a confined spaced, when one bifold door of a pair isclosed before the other, will not cause opening movement of the other,novel latches 44 and 45 may be utilized. These latches are attached toeach bifold door panel at the mid-region of the hinge axis at which thepanels are connected, and may comprise aligned and releasably connecteddetent elements 46 and 47 for the panels 13 and 14 and releasablyconnected detent elements 48 and 49 for the panels 15 and 16. In thisinstance, it is contemplated that the releasably connected detentelements are offset, in each instance, from the hinge axis in adirection such that they are brought together in coupling relationshipwhen the panels of a bifold door are in coplanar relationship, and arepulled apart when the panels of the bifold door are swung into angularrelationship, so as to separate the adjoined edges of the door panels.

Having particular reference to the hinge structures, as depicted inFIGS. 2, 3, 4a, 4and 5, each hinge has two unitary or integral elements50 and 52, both of which are adapted to be produced of thermoplasticmaterial, such as nylon, molded under pressure in a suitable die.Furthermore, the hinges used at the top and bottom positions on eachbifold door are alike, except that the elements are reversed from sideto side and inverted between the positions. Thus, a description of thestructure of one hinge will suffice for all. A hinge being thus made,need only be positioned relative to a door for use, as will be morefully described.

In the form illustrated, the hinge elements 50 and 52, in addition tobeing unitary, have bodies 53 and 54 respectively adapted to productionby molding. The hinge bodies have mounting plate portions 55 and 56 atone end, the inner surfaces of which, as used, serve as mountingsurfaces 57 and 58, which, when the hinge element is mounted, engage atop end surface, such as 60, 62 or a bottom end surface, such as 63 or64 of the door panel on which the element is mounted. The hinge elementbodies 53 and 54 also include plug-type mounting portions 65 and 66which project from the mid-regions of the mounting surfaces 57 and 58 onthe mounting portions 55 and 56.

The plug-type mounting portions 65 and 66 have generally cylindricalsurface portions 67 and 68 respectively which, when installed on a doorpanel fit snugly in openings in the edges of the adjacent panels whichare to be connected by the hinge, which openings are selectively andprecisely placed in the panels thereby to serve in properly locating thehinge elements on the panels. In addition, the hinge elements 50 and 52,in this preferred hinge structure, have flanges 69 and '70 which areintegral with the mounting plate portions 55 and 56 and project insubstantially right angular relation to the mounting surfaces 57 and 58in spaced and parallel relation to the plug-type mounting portions 65and 66 respectively. When the hinges are mounted with their plug-typemounting portions in their respective panel openings, the flanges engageexternal planar surfaces of the panels and serve additionally to locateand orient each hinge element with its respective door panel. Althoughthere are other reasons in respect to the hinge structure disclosed, itis preferred that the flanges 69 and 70 are disposed to engage the rearor inner surfaces of the door panels, as shown in FIGS. 1, 2 and 3, sothat visible hinge structure is as inconspicuous as possible.

In order that the panels of each bifold door may swing outwardly, asshown in FIG. 8, and effect separation of edges 74 and 75 which abutwhen the door panels are in a coplanar and closed position, the axis 76of each of the panel connecting hinges is displaced somewhat to the rearof the back panel surfaces 72 and 73, as shown in FIG. 3. Additionally,the hing axis 76 is aligned substantially with the edges 74 and 75, sothat those edges swing in practical radial relationship relativethereto.

For the accomplishment of this hinge axis placement, and to obtain therequired hinge'support for the connected panels in the disclosedstructure, the flange 70 on the hinge element 52 has an end projection77 extending beyond the edge 75, and which, at its top, is at a levelbelow the top of the mounting plate portion 56, and serves as a supportor bearing suface 78. A bearing bore 79 which establishes the hinge axisfor the hinge element 52 extends into the end projection 76 on theflange, through the bearing surface 78 thereof at a positionsubstantially aligned with edge 75 and rearward of the door panelengaging surface of the flange 70. Since the level of the bearingsurface 78 is below the top of the mounting plate portion 56, a shoulder80 extends across the flange and between the top of the flange endprojection 77 and the top of the mounting plate portion 56.

On the hinge element 50, a projecting arm 82 is provided on the mountingplate element 55 which extends rearwardly therefrom and also beyond theline of the edge 74. This arm 82 on the hinge assembly 50 has athickness such that when resting against the bearing surface 78 on thehinge element 52 in the hinge assembly, the mounting surfaces 57 and 58of the two hinge elements of the assembled pair are substantiallycoplanar. Although other types of hinge pins, such as metal, may beused, the disclosed embodiment has a hinge pin 83 integrally moldedthereon and projecting from the arm 82 for rotational engagement in thebearing bore 79 to adjoin the hinge elements for relative swingingmovements. It may be observed that the arm 82 has a rounded end surfacepermitting it to turn in the space adjacent the shoulder 80 on the hingeelement 52, and also that the back surface of the arm 82 is angularlydisposed to provide for ample swinging movement between the hingeelements.

For mounting and securing the hinge elements 50 and 52 on door panels,it is an expectation that the plug-type mounting portions 65 and 66 willbe press fitted into generally circular openings in the panels. Themounting openings will snugly fit the cylindrical surface portions 67and 68 of the mounting portions. In order to provide a deterrent torotation of the mounting portions in their respective openings,outwardly projecting splines 84 of generally triangular section extendlongitudinally of the cylindrical surface portions which splines breakthe cylindrical surface contours and depress themselves into thesurrounding material when installed.

While other structural arrangements are obviously available, theplug-type mounting portions shown are provided at their mid-regions withelongated flat surfaces 85 and 86 in opposedrelationship. At theopposite ends of the flat surface 85, notches 87 and 88 are provided,while at the-opposite ends of the flatsurface 86, notches 89 and 90 areprovided; such notches being in opposed relationship and opening towardthe flat surface, as well as being open at opposite sides.- Thesenotches, or equivalent means, are used to fasten metal spring elements92, of the type shown in FlG. 9 in operating position. Each such springelement has a generally flat back surface which mounts against the flatsurfaces 85 and 86 of the mounting portions. Each spring element haspunched therefrom a plurality of tangs 93 in a row and extending inangular relationship to the back surface of the strip. Each tang isnotched to present sharp points 94 at its projecting end. When mountedon the plug-type mounting portions of the hinge elements, the tangs 9357 and 58 of the mounting plate portions. When'each plug-type mountingportion is pressed into a mounting opening of a door panel, the tangsflex inwardly to afford ease of mounting, and when once set, the sharptang end points bite into the door panel material to prevent extractionof the hinge element from the door panel.

From the foregoing description, and by reference to the drawings, it maybe readily understood that the hinge of this invention has manyadvantages, particularly for a type of relatively lightweight doors,such as bifold closet doors and the like. Being made in standard sizesfor selected door panel thicknesses, the panels may be fabricated ordrilled by inexpensive operations -to receive the hinges without furthercutting, fitting, or

drilling at the time of instllation. During installation, or even whenthe door panels are fabricated, the hinge elements can be quickly andeasily installed. Being reversible for use at either end of a door, theinventory of hinge parts is minimized. Since the structures of the mainparts adapt them to production of relatively small quantities ofpressuremoldable plastic material, the hinges can be produced at low cost. It isa further feature that the hinge of this invention both locates andorients itself at the time of installation.

I claim:

1. A hinge of a type suited for use in connecting planar panels offolding doors for relative swinging movements about a hinge axis spacedoutwardly of the planar panel surfaces and in substantial alignment withadjacent side edges of the panels connected by the hinges, saidconnected panels also being relatively swingeable about said hinge axisfrom and toward coplanar positions in which said adjacent side edgesthereof are in substantial abutment with one another, said hingecomprising a pair of hinge elements which each include means throughwhich the elements are connected for relative swinging movements aboutthe aforesaid hinge axis, said hinge elements having mounting plateportions which, when the elements are connected, have reference surfacesin coplanar relationship to one another, each said mounting plateportion having a plugtype mounting portion thereon and projecting inperpendicular relationship from the mid-region of said referencesurface, and each said mounting plate portion also having a referenceand locating flange thereon which extends in right angular relationshipto the reference surface from one margin of the mounting plate portionin spaced and parallel relationship to said plugtype mounting portion.

2. A hinge as defined in claim 1 and wherein said means through whichthe elements are connected for relative swinging movement are disposedon the same side of the mounting plate portions as said mounting andlocating flanges.

3. A hinge as defined in claim 1, and further characterized by means onsaid plug-type mounting portions for resisting the removal thereof fromclosely fitting door panel openings into which they are inserted.

4. A hinge as defined in claim 1, and wherein said means through whichthe elements of each pair of hinges are connected for relativelyswinging movements comprise a portion projecting from one of the hingeelements of the pair and having a support surface substantially flushwith the reference surface thereof, said flange of the other hingeelement having another support surface thereon and substantially flushwith the reference surface thereof, said portions of the pair of hingeelements being disposed to overlap when the hinge elements areassembled, and means connecting said projecting and flange portions ofthe hinge elements for relatively swinging movements when the supportsurfaces thereof are in contact.

5. A hinge as defined in claim 4, and wherein said means connecting saidprojecting and flange portions of the hinge elements comprises an.integral hinge pin on the projecting portion of one of the hingeelements which fits rotationally into a bearing opening in the flangeportion of the other hinge element of the pair.

6. A hinge suited for use for connecting planar panels of folding doorsand the like for relative swinging movements and adapted to mountingagainst top and bottom end edge surfaces of said panels, said hingescomprising a pair of hinge elements, said hinge elements having mountingplate portions which have thereon mounting surfaces that are insubstantially coplanar relationship when the hinge elements areassembled and which have thereon mounting surfaces for engagement withthe end surfaces of adjacent door panels connected by the hinge, saidmounting plate portions each having thereon a plug-type mounting portionprojecting in perpendicular relationship from the mounting surface forthe location and securement of the hinge element relative to a doorpanel, projections on said mounting plate portions and extending topositions spaced outwardly of the hinge from adjacent end edges of thehinge elements when assembled, said projections having thereon surfaceswhich are engageable in overlapping relationship as doorpanel-supporting surfaces when the hinge elements are assembled, andmeans connecting said projections for rotationally swinging movements.

7. A hinge as defined in claim 6, and wherein said mounting plateportions have thereon means for effecting orientation of the respectivehinge elements with surfaces of the door panels upon which they aremounted.

8. A hinge as defined in claim 6, and wherein each of said plug-typemounting portions has an external noncircular perpendicular surfaceconfiguration.

9. A hinge as defined in claim 6, and wherein said adjacent end edges ofthe hinge elements are in adjacent and closely spaced relationship whenthe hinge elements are relatively disposed to provide substantiallycoplanar relationship of panels connected thereby, and said meansconnecting said projections for rotationally swinging movements beingdisplaced laterally from the panels thus connected.

it). A hinge for connecting planar panels of folding doors and the likefor swinging movements relative to one another and adapted to mountingat precisely located positions near adjacent side edges of said panels,said hinges comprising a pair of hinge elements, each of said hingeelements including a unitary and integral molded body having a mountingplate portion, one surface of which mounting plate portion serves as amounting surface engageable with one surface of a door panel, said bodyfor further having a plug-type mounting portion projecting insubstantially perpendicular relationship from the mid-region of themounting surface on the mounting plate portion, said mounting plateportions of the two elements of a pair having projections thereon atdifferent levels and for engagement in overlapping relationship asrelative supporting surfaces when the pair of elements is assembled, andmeans providing a hinge pin connection between said side projections ofthe elements of the pair to join the elements for swinging movementsabout an axis Clisplaced from said mounting plate and plug-type mountingportions.

11. A hinge as defined in claim 10, and wherein said plug-type mountingportions have non-circular peripheral contours to prevent rotationthereof when pressed into an opening in a door panel.

12. A hinge as defined in claim 10, and further characterized by meanson opposed side surfaces of the plug-type mounting portions and havingintegral tangs projecting angularly therefrom in a direction outwardlyfrom the plug-type mounting portions and toward the mounting surfaces toresist removal of the hinge elements from panels after the plug-typemounting portions are pressed into openings in the door panels.

13. A hinge as defined in claim 10, and further characterized by meanson each of the hinge elements for determining the position of thatelement peripherally of the plug-type mounting element with respect tothe panel on which it is mounted.

14. A hinge as defined in claim 10, and further characterized by aflange on the mounting plate portion of each hinge element and extendingin angular relationship to said mounting surface and spaced from theplug-type mounting portion for engagement with an external surface ofthe panel other than said one surface upon which it is mounted andangularly disposed relative thereto.

3,813,730 June 4, 1974 Patent No. Dated Inv entor(s) Lester L. Smith Itis certified that error appears in the above-identified patent 4 andthat said Letters Patent are hereby corrected as shown below:

Col. 1, line 24, "whould" should be --should Col. 1, line 54, after"panels" the word "to" should be -of-- Col. 2,. line 10, after "with"insert "the" (fol. 4, line 33, after "4" insert "b" 601. 5, line 20,"hing" should be hinge-- Col. 6, line 25, after "93" insert "projectoutwardly therefrom and toward the mounting surfaces" Col. 8, line 6,"perpendicular" should be ---peripheral I Col. 8, line 24,- after "body"delete "for" claim 10, line 9) Col. 8, line 28,- after "having" insert"side" Signed and sealed this 5th dayof November 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. C, MARSHALL DANN Attesting Officer Commissionerof'Paten-ts )RM USCOMM-DC 60376-P59 US. GOVERNMENT PRINTING OFFICE I 9690-366-33,

1. A hinge of a type suited for use in connecting planar panels offolding doors for relative swinging movements about a hinge axis spacedoutwardly of the planar panel surfaces and in substantial alignment withadjacent side edges of the panels connected by the hinges, saidconnected panels also being relatively swingeable about said hinge axisfrom and toward coplanar positions in which said adjacent side edgesthereof are in substantial abutment with one another, said hingecomprising a pair of hinge elements which each include means throughwhich the elements are connected for relative swinging movements aboutthe aforesaid hinge axis, said hinge elements having mounting plateportions which, when the elements are connected, have reference surfacesin coplanar relationship to one another, each said mounting plateportion having a plug-type mounting portion thereon and projecting inperpendicular relationship from the mid-region of said referencesurface, and each said mounting plate portion also having a referenceand locating flange thereon which extends in right angular relationshipto the reference surface from one margin of the mounting plate portionin spaced and parallel relationship to said plug-type mounting portion.2. A hinge as defined in claim 1 and wherein said means through whichthe elements are connected for relative swinging movement are disposedon the same side of the mounting plate portions as said mounting andlocating flanges.
 3. A hinge as defined in claim 1, and furthercharacterized by means on said plug-type mounting portions for resistingthe removal thereof from closely fitting door panel openings into whichthey are inserted.
 4. A hinge as defined in claim 1, and wherein saidmeans through which the elements of each pair of hinges are connectedfor relatively swinging movements comprise a portion projecting from oneof the hinge elements of the pair and having a support surfacesubstantially flush with the reference surface thereof, said flange ofthe other hinge element having another support surface thereon andsubstantially flush with the reference surface thereof, said portions ofthe pair of hinge elements being disposed to overlap when the hingeelements are assembled, and means connecting said projecting and flangeportions of the hinge elements for relatively swinging movements whenthe support surfaces thereof are in contact.
 5. A hinge as defined inclaim 4, and wherein said means connecting said projecting and flangeportions of the hinge elements comprises an integral hinge pin on theprojecting portion of one of the hinge elements which fits rotationallyinto a bearing opening in the flange portion of the other hinge elementof the pair.
 6. A hinge suited for use for connecting planar panels offolding doors and the like for relative swinging movements and adaptedto mounting against top and bottom end edge surfaces of said panels,said hinges comprising a pair of hinge elements, said hinge elementshaving mounting plate portions which have thereon mounting surfaces thatare in substantially coplanar relationship when the hinge elements areassembled and which have thereon mounting surfaces for engagement withthe end surfaces of adjacent doOr panels connected by the hinge, saidmounting plate portions each having thereon a plug-type mounting portionprojecting in perpendicular relationship from the mounting surface forthe location and securement of the hinge element relative to a doorpanel, projections on said mounting plate portions and extending topositions spaced outwardly of the hinge from adjacent end edges of thehinge elements when assembled, said projections having thereon surfaceswhich are engageable in overlapping relationship as door panelsupporting surfaces when the hinge elements are assembled, and meansconnecting said projections for rotationally swinging movements.
 7. Ahinge as defined in claim 6, and wherein said mounting plate portionshave thereon means for effecting orientation of the respective hingeelements with surfaces of the door panels upon which they are mounted.8. A hinge as defined in claim 6, and wherein each of said plug-typemounting portions has an external non-circular perpendicular surfaceconfiguration.
 9. A hinge as defined in claim 6, and wherein saidadjacent end edges of the hinge elements are in adjacent and closelyspaced relationship when the hinge elements are relatively disposed toprovide substantially coplanar relationship of panels connected thereby,and said means connecting said projections for rotationally swingingmovements being displaced laterally from the panels thus connected. 10.A hinge for connecting planar panels of folding doors and the like forswinging movements relative to one another and adapted to mounting atprecisely located positions near adjacent side edges of said panels,said hinges comprising a pair of hinge elements, each of said hingeelements including a unitary and integral molded body having a mountingplate portion, one surface of which mounting plate portion serves as amounting surface engageable with one surface of a door panel, said bodyfor further having a plug-type mounting portion projecting insubstantially perpendicular relationship from the mid-region of themounting surface on the mounting plate portion, said mounting plateportions of the two elements of a pair having projections thereon atdifferent levels and for engagement in overlapping relationship asrelative supporting surfaces when the pair of elements is assembled, andmeans providing a hinge pin connection between said side projections ofthe elements of the pair to join the elements for swinging movementsabout an axis displaced from said mounting plate and plug-type mountingportions.
 11. A hinge as defined in claim 10, and wherein said plug-typemounting portions have non-circular peripheral contours to preventrotation thereof when pressed into an opening in a door panel.
 12. Ahinge as defined in claim 10, and further characterized by means onopposed side surfaces of the plug-type mounting portions and havingintegral tangs projecting angularly therefrom in a direction outwardlyfrom the plug-type mounting portions and toward the mounting surfaces toresist removal of the hinge elements from panels after the plug-typemounting portions are pressed into openings in the door panels.
 13. Ahinge as defined in claim 10, and further characterized by means on eachof the hinge elements for determining the position of that elementperipherally of the plug-type mounting element with respect to the panelon which it is mounted.
 14. A hinge as defined in claim 10, and furthercharacterized by a flange on the mounting plate portion of each hingeelement and extending in angular relationship to said mounting surfaceand spaced from the plug-type mounting portion for engagement with anexternal surface of the panel other than said one surface upon which itis mounted and angularly disposed relative thereto.